- [Goldstein] We have 17,000 trucks.
What do you think it would take
to take a quarter of those offline
and charge them overnight?
What would the utility requirements be like?
- We are talking about batteries versus hydrogen cars.
Hey, I'm Dianna, you're watching Physics Girl.
We are back with our renewable energy series.
My production team and I went on a road trip
around California, surviving just on hydrogen.
By the way, thank you to Toyota
for sponsoring this entire series.
(whispering) And for giving us the keys for the car.
This one is about hydrogen in transportation.
Specifically, we're going to compare
battery-electric vehicles to hydrogen.
I mean, okay, hold on, step back.
Why are we doing this video?
I care about the environment,
but the way that you show you care is you learn,
and so I went and did that.
There's battery-powered electric vehicles,
and then there's these fuel cell electric vehicles.
They're both electric vehicles,
so if you say an EV, you're talking about both, technically.
And we learned that people love to compare,
even though hydrogen people love talking about
how people love comparing them.
Battery-electric vehicles are here, right?
They have caught on.
So my first question
when we got into the hydrogen fuel cell car was,
"Okay, why do we need hydrogen?"
I didn't even know that hydrogen fuel cell cars
were on the road, which they are in California
and in a number of other countries.
I'm focusing a lot of this discussion on California.
So, let's start the competition
between battery-electric vehicles
and fuel cell electric vehicles.
I'm gonna start with driving range.
How far can you go in these cars?
Most electric vehicles...
Battery electric.
See? I did it.
So most battery-electric cars can go
between about 100 and 200 miles,
one of the higher end battery-electric cars
can go about 387 miles.
Hydrogen cars are averaging about a 300 mile range,
so they're already getting up toward
the best battery cars,
and the 2021 Mirai XLE,
which it another version of the car
that we were driving,
has an EPA-estimated range of 402 miles.
So they're pretty close in driving range,
but let's move on the refueling,
and it's gonna get a lot more complicated.
Refueling time, let's talk about the time.
To refuel a battery-electric vehicle,
it's on the order of hours.
If you're using the super fast chargers,
it could be as little as a half an hour.
When you're refueling with hydrogen,
it takes about five minutes.
But one thing we talked about in the last video is that
the experience driving a hydrogen car
had so much to do with thinking about
where the stations are.
We actually visited the very first hydrogen station
in California in order to meet up
with the director of the Advanced Power and Energy Program
at UC Irvine.
- The first station here,
and the first one in the United States,
was in January
of 2003.
- So now, it is May 2021,
there are 45 hydrogen stations in California.
So for comparison on the numbers,
5,000 super-charging stations,
and there are about 45 hydrogen stations in California.
So the one thing I will say is like,
if a hydrogen station is down,
that adds a lot of time to your refueling time.
Battery-electric vehicles went through that phase as well.
They're a lot further along in their
ascent to the mainstream.
So, there's about 15 million cars,
and 250,000 of them are battery-electric.
Then there's 8,000 fuel cell cars.
That's how new the hydrogen technology is.
- [Samuelsen] We have now about 8,000 cars
on the road in California.
- So we started with hybrid-electric vehicles
in kind of like the 90's or so.
Those took off like a hockey stick.
- Where you're coming up,
and not quite going up this way in the market.
In energy, we talk about that as being a
curled development time,
and then you get to a point, we call the activation energy,
when the market self-propagates, it just grows.
- That's what we're seeing now
with these fuel cell and battery-electric vehicles.
- You sort of saw this with electric cars, actually,
but the crook of the stick was in about 2012.
Hydrogen is obviously a lot further behind.
- There's, I think, about 8,000 gasoline stations
for cars in California.
So by doing some work and actually figuring out
how many you would need to cover that same amount,
it's maybe about 1,000 stations.
And it could be co-located at gasoline stations.
- The other thing to consider is where you can refuel.
- 50% of people here live in multi-family housing.
We don't all have garages, we don't all have parking spots,
we don't all work at forward-leaning technology company
that lets us charge for free
when we drive our electric vehicles to work,
right? - [Dianna] Yeah yeah, exactly.
I live with roommates, and I cannot put a charger
into the house that I rent.
But, I could do hydrogen
if there were a station close enough to where I live.
So what have we got?
We've got the stations are very few and far between,
it can be much more convenient to charge at home,
but not everyone lives in a home that they own
where they can put a charging station.
Everybody loves a competition.
So, let's move on to efficiency.
So if we first look at the specific energy
of hydrogen versus batteries,
and that is a measure of the amount of energy
you get per weight.
With hydrogen, it's 35,000 watts per kilogram.
With batteries, I'm talking about lithium-ion batteries,
it's 200, best case kinda close to 300.
But the overall efficiency of hydrogen is 25 to 35%,
whereas battery-electric vehicles is 70 to 90.
25 to 35 versus 70 to 90.
So let's look now at the losses that happen.
So in order to get energy to charge your batteries,
you have to produce the electricity
somewhere at a power plant,
then it's sent down the transmission lines
and there's some loss of energy in that process.
And then a small amount is lost to charging the battery,
and then somewhere in there,
there's AC to DC conversion loss,
and then a loss getting the electricity
from the battery to the wheels.
You're looking at a total loss
or a total efficiency of 70 to 90% for batteries.
So for hydrogen, if you do electrolysis,
which is the cleanest way of getting the hydrogen,
you lose 30% of your energy.
If you use the proton exchange membrane,
it'd be a bit more efficient,
but those are, again, still more in the development stage.
And then, you lose energy compressing the hydrogen,
or cooling it, and then in transporting it.
And then there's a significant loss
going from the fuel cell to the wheel.
Add all of that up and you're looking
at a 25 to 35% efficiency for fuel cells.
And it's mostly things that you can't get around,
which means you have to use
about twice as much energy to produce hydrogen
and then to use hydrogen for your cars
as you do to produce electricity for your battery cars.
The other thing to consider with efficiency
is that batteries lose capacity over time.
That doesn't happen nearly as much
with fuel cell electric vehicles.
Let's look at other uses within transportation
for batteries and hydrogen besides just passenger cars.
- The beauty of a fuel cell, it's so modular and scalable.
So you can go down to...
There's literally products that charge your phone,
like a little, tiny little fuel cell
that charges your phone,
all the way up to something like a plane.
- Batteries are scalable too!
You can put them in your phones, your computers,
your Trucklas.
So the general consensus is that
both batteries and fuel cells
are great for uses in transportation,
even beyond passenger cars,
but when it comes to carrying more weight,
going farther, going faster,
fuel cells have the advantage.
And the reason why is because of one graph,
and I'm gonna show it to you guys right now.
What you're seeing here is...
On this axis, you're seeing the vehicle test weight,
so that's how heavy the vehicle is,
and then over here, you're seeing the range.
So fuel cell and battery-electric vehicles
start at about the same.
It's worse than a linear scale upwards
as you increase the range of lithium-ion battery vehicles.
When you get up to 400 miles,
you're looking at a difference of about 1,500 kilograms.
One of the people that we talked to
was from a non-profit called Energy Independence Now
that is aiming to move away from petroleum-dependence,
and we talked about the type of cars that people use.
- Where I lived in Colorado,
people really used these vehicles to their full capacity.
Four-wheel drive, every weekend, four people,
dogs, skis, snowboards on top of the cars.
Really have to give consumers what they want
if we expect to be successful.
- The hydrogen has a very high
gravimetric energy storage density,
so as you add more range to the vehicle,
you're not also adding more weight.
Whereas with battery-electrics,
there is kind of a tipping point
where you're just adding more weight
and therefore you can't get more range.
- And that's just in the 400 mile range,
and that's the range we're looking at
for passenger vehicles.
- Well I feel excited about it,
the fact that it allows people to have choice.
It's so flexible.
Some of my research has been looking at
other sectors other than on-road,
so looking at ships and looking at rail.
- And Toyota, among other auto manufacturers,
are already testing big rig fuel cell trucks.
We actually got to see one.
We went to visit one in the port at Long Beach.
- You know, some of the differences
that I see as a driver,
one would be the quietness of the fuel cell itself is.
If you have a passenger,
you literally can converse with them.
- We're seeing just about every major truck auto maker
is developing fuel cells right now.
So between the likes of Daimler, Volvo,
Freightliner, Mac, all of them
kind of funneling in and getting onto
the development of fuel cells.
Even startup companies, Hyzon, Nicholas.
- Is anyone working on battery-electric trucks?
Yes, Tesla's working on them.
Both can be promising though.
There are added bonuses to going electric
for all of these uses.
- Pretty amazing that this is zero emissions.
What we're trying to do for the environment
with these trucks is to take the smoke out of the air.
- I got to see a hydrogen-powered boat!
- I got to drive this boat today.
I thought it was cool, and I was really excited about it,
and I realized, this boat is completely silent.
- Seems like, from what most people we talked to said,
there are more promising uses for fuel cells
in other areas of transportation,
especially when it comes to higher weight,
higher range, higher speed.
So the infrastructure for the charging network
and the refueling network is not there,
and it's much less there for hydrogen
than it is for batteries.
There are just not enough hydrogen stations yet.
There's still some kinks to be worked out.
- We were having issues with the nozzles freezing up.
So we went from these like, very isolated applications
for these nozzles, where they were used, you know,
by professionals.
Everyday consumers were trying to use it
while they're talking on their phone
and bouncing a baby, or, you know.
We were experiencing these issues.
People for some reason decided
that pouring water on a frozen nozzle
would thaw it out,
wherein in fact, it was just getting more moisture
inside the nozzle and it was causing it
to freeze more. (Dianna groaning)
- Where we need work is on the equipment
to have it be more reliable,
so the new stations will have more than one dispenser.
- If we replaced all 15 million cars in California right now
with electric vehicles, and plugged them all in
at the same time at night, the grid would fail.
- Well hey, we have 17,000 trucks
at the Twin Ports here.
What do you think it would take
to take a quarter of those, you know, 4,000 trucks offline
and charge them overnight?
What are the economic impacts
of taking 4,000 trucks off-duty
to charge for, whatever, four hours, 12 hours,
however long it takes?
You know, when you look at scale that large.
- But if instead you had some of those people charging
and plugging in, and then some people could go to
a nearby hydrogen station,
in some places, it's gonna make more sense
to upgrade your electrical grid.
In other places, it's gonna make a lot more sense
to install a hydrogen station.
- My "ah hah" moment, when I was working in Japan,
I was commissioning a station
and you would have a Mirai customer come up
and then a (indistinct) customer come up
and just fill one after another.
Five minutes, five minutes, five minutes,
and there goes another zero-emission vehicle.
It made so much sense.
- There are really interesting considerations
from an infrastructure perspective.
How many people can charge,
where they can charge,
or how many people can refuel,
where they can refuel.
- So we take a look at
kind of user behavior from proxy vehicles
like battery-electric and hybrid-electric
'cause we think those are the type of drivers
who might also be willing to adopt and drive
a fuel cell vehicle.
- Energy diversification is so important.
The more diversification you have,
the more security you have.
If there's a hydrogen shortage,
you can charge an electric car.
Or, for whatever reason, the electrical grid is down,
if you have hydrogen cars available,
you can go refuel hydrogen.
- During the middle of the day was more renewables
like solar and wind.
We can absorb those renewables
and absorb those electricity,
store it in the batteries,
and then during the night when the sun is not shining
and the wind is not blowing, we can...
Then we use that electricity.
And then discharge that back to the buildings
or homes or the electric grid.
- I think it was echoed by most people we talked to,
there are no winners or losers.
- The majority of questions that we are asked is,
"What about the battery-electric vehicle, the BEV?"
"Is that gonna win,
or is this fuel cell electric vehicle
gonna win?" - [Dianna] Yeah!
- But it turns out, they're both gonna be winners
because they're both going to be needed.
- So I grew up in China,
and smog was like a really big thing in China,
and that's what made my mind into like,
"Okay, we gotta find a way to like,
reduce the air pollutants."
- This like, competitive nature
that we all have as Americans,
of like wanting to pick this winner,
and I just wanna like scream from the hilltops
like, "Hey, we need both of these!"
- We're not only addressing the climate,
but we're also addressing that poor air quality.
We're providing a lot of health benefits.
Seeing the change has been really great.
- Thank you so much for watching.
Stay tuned for the next video of the series,
which is going to be about energy storage.
Thank you to Toyota for sponsoring this series,
and happy physicsing.
(upbeat, engaging outro music plays)